Cancer Margin Detection using Infrared Spectroscopy and Plasmon Resonance Abstract While surgical resection of cancerous tissue is the single most effective treatment for many forms of human cancer, the effectiveness of surgical procedures is limited by the difficulty of accurately recognizing tumor margins. Thus, the development of cancer specific molecular surface probes using ex vivo immunohistochemistry (IHC) is highly desirable. In the proposed studies, infrared (IR) spectroscopy with surface plasmon mesh enhancement will be used to assess normal versus adenocarcinoma tissues. This technology provides molecular signatures of biological tissue. Moreover, we will utilize labeled IR reporter molecular systems that consist of deuterated polyethylene glycol (dPEG) molecules synthetically attached to anti-tumor-associated-glycoprotein- 72 (anti-TAG-72), which selectively co-locates with adenocarcinoma tissue. This addresses the critical need for ex vivo differentiation between normal and cancerous tissue during surgery. IR methods, specifically with surface plasmon enhancement mesh materials that have highly reproducible IR absorbances, have the potential to overcome the limitations of current time consuming and labor intensive histological procedures. The specific molecular characterization of tumor margins will be more precise and reliable than current methods which depend on visual inspection of tumor biopsy material. Advanced IR methods can enable thorough analysis of resected tumor tissue, increase the quality of operating room histological analyses, and guide complete surgical removal of cancerous tissue. The approach of this proposal is to construct dPEG labeled adenocarcinomo-specific anti-TAG-72 monoclonal antibodies (MAbs) and assess the use of these reporters to identify tumor margins. The combination of IR spectroscopy and labeled anti-TAG MAbs has the ability to reduce assessment time and to supply timely feedback to the surgeon. It can also reduce the needless destruction or removal of normal tissues, improving patient outcomes. Anti-TAG MAbs have been shown to be highly selective for colon, breast, and gynecological cancer tissues making this methodology applicable to a range of medically important human cancers. Human tissue samples from colon, breast and pelvic/genital tissues for this proposed research will be provided by a surgical oncology team comprised of Drs. Martin, Povoski, and O'Malley. The pathology team, Drs. Hitchcock and Allen, will lead the development of histological and analytical methods including procedures for tissue staining with reporter constructs. Additionally, Coe will lead the surface plasmon IR enhancement methodology strategies. Team members (PI team and surgical team) have an established working relationship in MAb development in past years and this current proposal brings together additional expertise in IR and enhancement technology that has shown to be synergistic.